<html>
  <head>
    <meta charset = 'utf-8'>
    <title>大傻逼</title>
    <script>
    function displaydate(){
    	document.detElementById("demo").innerHTML=Date();
    }

    </script>
  </head>

  <body>
  <h1>Hello Word!!</h1>
  <p id = "demo">这是一个段落!</p>
  <button type = "button" onclick = "displaydate()">显示日期按钮</button>
  </body>
<html>